The explosive spread of the Zika virus has captured our attention and dominated headlines. Of particular concern is the possible link between Zika virus infection and microcephaly. Meanwhile, worries about Ebola have diminished, with the World Health Organization declaring an end to the Ebola outbreak in West Africa. The frenzy that the Ebola virusgenerated in the United States during the fall of 2014 has become a distant memory. What lessons can we learn from our reaction to the Ebola threat, and how can we apply these lessons to Zika and future epidemics?

In many instances, our response to Ebola was irrational and over the top. We had scenes of schools being shut down for dubious reasons, cruise ships prevented from docking, images of workers "disinfecting" public spaces including bowling alleys, and mandatory quarantines for asymptomatic healthcare workers returning from West Africa. There is no denying that Ebola is a deadly disease, with a fatality rate of approximately 50% in infected individuals. However, since Ebola is not an airborne or insect-borne virus, the chances of an epidemic in the United States were essentially zero. Indeed, the risk of death from the influenza virus or the West Nile virus was much higher.

This overreaction to small risks is nothing new. Humans are terrible at assessing risk, routinely overestimating risks such as deaths due to shark attacks. According to psychologists, one reason for risk misperception is the "availability heuristic," a concept pioneered by the Nobel laureate Daniel Kahneman and the late Amos Tversky. "Availability" refers to the ease by which we can recall examples of risky events. Risks that are easily recalled (often due to extensive coverage) are overestimated while risks under our radar are underestimated.

How should we deal with this misperception of risk? Some feel it is acceptable to respond to risks with seemingly irrational actions — if those actions calm public fears. After all, while our fears may be irrational, they are still real. This approach is similar to the "monster spray" that parents give small children to combat fear of the dark. Harmless aerosols that kids can spray under their beds get rid of the "monster" hiding there. Similarly, irrational public actions may still be justified by acting as an "adult monster spray" for our anxieties.

Dr. Puneet Opal is a neurologist at Northwestern University Feinberg School of Medicine, where he is also a director of the Physician-Scientist Training Program. Dr. Ameet R. Kini is director of hematopathology and flow cytometry at Loyola University Chicago Stritch School of Medicine.